Genome-wide association studies (GWAS) have remarkably advanced insight into the genetic basis of schizophrenia (SCZ). Still, most of the functional variance in disease risk remains unexplained. Hence, there is a growing need to map genetic variability-to-genes-to-functions for understanding the pathophysiology of SCZ and the development of better treatments. Genetic variation can regulate various cellular functions including DNA methylation, an epigenetic mark with important roles in transcription and the mediation of environmental influences...

First, we describe the hallmark contributions of Irv Gottesman's pioneering scholarship for schizophrenia research including concepts of polygenicity, gene × environment interactions, epigenetics and the endophenotype concept. Gottesman and colleagues' twin studies showed that genes, not social factors, mediate schizophrenia risk. He then showed that schizophrenia is highly polygenic. Next, he introduced the concept of epigenetics into schizophrenia research. Gottesman then introduced the quantitative endophenotype concept...

We know a great deal about schizophrenia, but the current state of the art is one of uncertainty. Researchers are confused, and patients feel misunderstood. This situation has been identified as due largely to the fact that the dominant neurobiological perspective leaves out the person. The aim of the present article is to review and integrate a series of clinical, phenomenological, historical, cultural, epidemiological, developmental, epigenetic, and therapeutic phenomena in support of a suggestion that schizophrenia is above all a disorder of the person rather than of the brain...

Post-traumatic stress disorder (PTSD) is a mental disorder occurring in about 2-9% of individuals after their exposure to life-threatening events, such as severe accidents, sexual abuse, combat or a natural catastrophe. Because PTSD patients are exposed to trauma, it is likely that epigenetic modifications have an important role in disease development and prognosis. For the past two decades, abnormal expression of the epigenetic regulators microRNAs (miRs) and miR-mediated gene regulation have been given importance in a variety of human diseases, such as cancer, heart disease and viral infection...

The study of neuropathological markers in patients affected by mental/psychiatric disorders is relevant for the comprehension of the pathogenesis and the correlation with the clinical symptomatology. The neuropathology of Alzheimer's disease (AD) recognizes intraneuronal and extracellular neurofibrillary formation responsible for neuronal degeneration. Immunohistochemical studies discovered many interesting results for a better interpretation of the AD pathogenesis, while the "metal hypothesis" supports that metal ions might differentially influence the formation of amyloid aggregates...

Chemical exposures, pre- and neonatal infections, psychosocial stress, and the cross-generational cultural and epigenetic impacts of these and other toxicants become an integrated, sometimes synergistic, signal that can overwhelm essential neurodevelopmental regulation. We characterize that dynamic through statistical models based on the asymptotic limit theorems of control and information theories. Schizophrenia and autism emerge as two different 'phases' of pathological neurodevelopmental 'condensations' that impair the dynamic, shifting global workspace of normal mental function...

Starting from the Developmental Origins of Health and Disease (DOHaD) hypotheses proposed by David Barker, namely fetal programming, in the past years, there is a growing evidence of the major role played by epigenetic factors during the intrauterine life and the perinatal period. Furthermore, it has been assessed that these factors can affect the health status in infancy and even in adulthood. In this review, we focus our attention on the fetal programming of the brain, analyzing the most recent literature concerning the epigenetic factors that can influence the development of neuropsychiatric disorders such as bipolar disorders, major depressive disorders, and schizophrenia...

We review the hypotheses concerning the association between the paternal age at childbearing and childhood psychiatric disorders (autism spectrum- and attention deficit/hyperactive disorder) and adult disorders (schizophrenia, bipolar-, obsessive-compulsive-, and major depressive disorder) based on epidemiological studies. Several hypotheses have been proposed to explain the paternal age effect. We discuss the four main-not mutually exclusive-hypotheses. These are the de novo mutation hypothesis, the hypothesis concerning epigenetic alterations, the selection into late fatherhood hypothesis, and the environmental resource hypothesis...

Epigenetic mechanisms are an important heritable and dynamic means of regulating various genomic functions, including gene expression, to orchestrate brain development, adult neurogenesis, and synaptic plasticity. These processes when perturbed are thought to contribute to schizophrenia pathophysiology. A core feature of schizophrenia is cognitive dysfunction. For genetic disorders where cognitive impairment is more severe such as intellectual disability, there are a disproportionally high number of genes involved in the epigenetic regulation of gene transcription...

This review concerns epigenetic mechanisms and their roles in conferring interindividual differences, especially as related to experientially acquired and genetically driven changes in central nervous system (CNS) function. In addition, the review contains commentary regarding the possible ways in which epigenomic changes may contribute to neuropsychiatric conditions and disorders and ways in which epigenotyping might be cross-correlated with clinical phenotyping in the context of precision medicine. The review begins with a basic description of epigenetic marking in the CNS and how these changes are powerful regulators of gene readout...

Schizophrenia (SZ) and cancer (Ca) have a broad spectrum of clinical phenotypes and a complex biological background, implicating a large number of genetic and epigenetic factors. SZ is a chronic neurodevelopmental disorder signified by an increase in the expression of apoptotic molecular signals, whereas Ca is conversely characterized by an increase in appropriate molecular signaling that stimulates uncontrolled cell proliferation. The rather low risk of developing Ca in patients suffering from SZ is a hypothesis that is still under debate...

Attempts to discover genes that are involved in the pathogenesis of major psychiatric disorders have been frustrating and often fruitless. Concern is building about the need to understand the complex ways in which nature and nurture interact to produce mental illness. We analyze the epigenome in several brain regions from schizophrenic patients with severe cognitive impairment using high-resolution (450K) DNA methylation array. We identified 139 differentially methylated CpG sites included in known and novel candidate genes sequences as well as in and intergenic sequences which functions remain unknown...

GABAergic dysfunction in hippocampus, a key feature of schizophrenia (SZ), may contribute to cognitive impairment in this disorder. In stratum oriens (SO) of sector CA3/2 of the human hippocampus, a network of genes involved in the regulation of glutamic acid decarboxylase GAD67 has been identified. Several of the genes in this network including epigenetic factors histone deacetylase 1 (HDAC1) and death-associated protein 6 (DAXX), the GABAergic enzyme GAD65 as well as the kainate receptor (KAR) subunits GluR6 and 7 show significant changes in expression in this area in SZ...

SZGR 2.0 is a comprehensive resource of candidate variants and genes for schizophrenia, covering genetic, epigenetic, transcriptomic, translational and many other types of evidence. By systematic review and curation of multiple lines of evidence, we included almost all variants and genes that have ever been reported to be associated with schizophrenia. In particular, we collected ∼4200 common variants reported in genome-wide association studies, ∼1000 de novo mutations discovered by large-scale sequencing of family samples, 215 genes spanning rare and replication copy number variations, 99 genes overlapping with linkage regions, 240 differentially expressed genes, 4651 differentially methylated genes and 49 genes as antipsychotic drug targets...

Epidemiological studies suggest that exposure to prenatal stressors, including malnutrition, maternal immune activation (MIA), and adverse life events, is associated with increased risks of schizophrenia, autism spectrum disorder (ASD), and attention-deficit hyperactivity disorder (ADHD). However, the underlying pathophysiological mechanisms are unclear. The first trimester of pregnancy is particularly a vulnerable period. During this period, the self-renewal of neural stem cells and neurogenesis vigorously occur, and synaptic connections are partially formed in the telencephalon...

Environmental pollution is a global problem with diverse and substantial public health implications. Although many environmental (i.e., non-genetic) risk factors for schizophrenia and other psychotic disorders have been identified, there has been comparatively little research on pollution as a possible risk factor. This is despite the fact that gene-by-environment interactions and epigenetic mechanisms are now recognized as likely facets of the etiology of schizophrenia, and the fact that pollution could potentially mediate the association between urban birth/upbringing and elevated risk...

BACKGROUND: The etiology of autism spectrum disorders (ASD) is complex and multifactorial, and the roles of genetic and environmental factors in its emergence have been well documented. Current research tends to indicate that these two factors act in a synergistic manner. The processes underlying this interaction are still poorly known, but epigenetic modifications could be the mediator in the gene/environment interface. The epigenetic mechanisms have been implicated in susceptibility to stress and also in the pathogenesis of psychiatric disorders including depression and schizophrenia...

Sensitization is defined as a process whereby repeated intermittent exposure to a given stimulus results in an enhanced response at subsequent exposures. Next to robust findings of an increased dopamine synthesis capacity in schizophrenia, empirical data and neuroimaging studies support the notion that the mesolimbic dopamine system of patients with schizophrenia is more reactive compared to healthy controls. These studies led to the conceptualization of schizophrenia as a state of endogenous sensitization, as stronger behavioral response and increased dopamine release after amphetamine administration or exposure to stress have been observed in patients with schizophrenia...